When working with original text documents, a user may need to select a specific region of interest within the document to perform one or more various operations on the region such as cut, copy and/or erase. When selecting a region of interest (ROI) in a text document, sections of text can be selected by moving a cursor over the desired sections to highlight the selected sections. The user is then able to perform various operations on the highlighted sections. The sections of text are easier to select on original text documents since text documents have characters at specific locations in the document wherein a cursor moving over those locations can select those characters.
On some devices such as, for example, mobile devices, printed text documents may be captured as images so as to have an electronic copy of the documents which may be easier to manage than the physical paper copies. These electronic documents are different than the original text documents because they are in an image format and therefore have no text information with which a cursor may be used to easily select regions of interest using the typical movement as discussed above and as is known in the art. In a captured image of a text document, there are no inherently-provided character locations to enable cursor selection.
To obtain text information and enable the user to select a region of interest in an image, optical character recognition (OCR) may be performed. However, OCR can be an expensive operation. An OCR operation typically starts by attempting to identify connected components representing characters then performing a correlation to identify what the characters represent. Other operations such as dictionary searches are also performed to reconstruct the original text, thereby allowing the user to select regions of interest in the now reconstructed image document having text information. However, this additional processing may be unnecessary when performing a straightforward selection of a region of interest in an image. With devices having limited processing capabilities and power supply such as mobile devices, the additional processing to be performed in an OCR operation may be a significant burden when a user only requires a simple selection of a region in the image.
An alternative method of selecting a region of interest in an image is to use the cursor to encircle the desired ROI. The area may be encircled or the circle itself may be highlighted to indicate the selection and operations such as crop or erase may then be performed to the selected area. Accurately drawing a circle or another polygon around the region of interest may be difficult to do using non-traditional cursors such as those controlled by human fingers on touchscreen devices. Thus, poor selection results that are prone to errors may occur when this method of selection is used.
Accordingly, a need exists in the art for methods of accurately selecting text in an image of a document that correspond to a familiar method used in selecting text in original text documents without performing unnecessary operations such as those required in a typical OCR operation. One or more methods of accurately selecting a region of interest in an image using familiar or intuitive cursor movements typical to selecting a region of interest in a text document is needed in the art. Additional benefits and alternatives are also sought when devising solutions.